
import 'reflect-metadata'
function Injectable(taregt){}

class Cd {
    showName(){
        console.log(111)
    }
}
@Injectable
class Dd{
    constructor(private a:string, private b: Cd){}
}
const a = Reflect.getMetadata('design:paramtypes',Dd)[1]
const b = new a()
b.showName()
console.log(b)